Angular position controller for clam-shell bucket

ABSTRACT

A clam-shell bucket comprises two jaws which are opened and closed by means of a fluid-actuated ram. The angular position of the jaws is controlled by means of a motor which is coupled to the jaws via a drive shaft extending into an axial cavity in a piston rod of the ram.

v United States Patent [1 1 [111 3,881,263 Coeurderoy May 6, 1975 ANGULAR POSITION CONTROLLER FOR [56] References Cited CUM-SHELL BUCKET UNITED STATES PATENTS [75] Inventor: Yves G. Coeurderoy, Lagny-le-Sec, 3,314,709 4/1967 Guinot 294/70 France 3,493,135 2/1970 Novotny 214/147 G 3,527,495 9/1970 Marad n 294/106 X [731 Asslgnee! Anonymm PwmLe Plessls 3,727,968 4/1973 Tsuchihashi et a1. 294/88 Bellevllle, France 3,759,564 9 1973 Seaberg 294/88 [22] Filed: Mar. 11, 1974 Primary ExaminerCliff0rd D. Crowder [21] Appl. No.: 449,609 Attorney, Agent, or FirmFitzpatrick, Cella, Harper & Scinto [30] Foreign Application Priority Data Apr. 18, 1973 France 73.14238 ABSTRACT A clam-shell bucket comprises two jaws which are U-S- Cl. opened and closed means of a fluid-actuated ram 294/88 The angular position of the jaws is controlled by lnt. means of a motor is coupled to the jaws via a [58] Field of Search 37/182, 183 R, 183 A, 184,

37/185, 186, 187, 188; 294/70, 86 R, 88, 106, 115; 214/656, 657, 658,147 R, 147 G .llllllllll llllllllll 1 drive shaft extending into an axial cavity in a piston rod of the ram.

10 Claims, 3 Drawing Figures mEmEnMAY 8191s I 3.881.263

SHEET 10F 2 ANGULAR POSITION CONTROLLER FOR CLAM-SI-IELL BUCKET BACKGROUND OF THE INVENTION 1. Field of Invention The present invention relates to clam-shell buckets.

2 Description of the Prior Art It has been proposed to provide clam-shell buckets with an orientating motor to enable them to be easily placed in a particular position with respect to the material to be picked up. When opening of the buckets is controlled by a ram, sliding movement of the cylinder rod of the ram relative to the cylinder of the ram generally requires complicated, heavy and costly arragements.

SUMMARY OF THE INVENTION According to the present invention, there is provided a clam-shell bucket comprising grasping elements, ram means for adjusting the position of said elements, said ram means comprising a cylinder having opposed end walls piston means slidable on the cylinder, and piston rod means carried by the piston means, said piston rod means including a central cavity open at at least one end of the piston rod means, motor means operative to adjust the angular orientation of the grasping elements, said motor means comprising a body member, and a shaft member rotatable relative to the body member, and rotary driving rod means, one of said members being rigid with an end portion of the piston rod means and the other of said members being coupled with the driving rod means, said driving rod means extending into the said cavity through the open end thereof.

Further according to the present invention, there is provided a clam-shell bucket comprising jaws, a fluidactuated ram operative to open and close jaws, said ram including a cylinder having opposed end walls, and piston rod means movable in the cylinder an extending through the end walls, said piston rod means having an axial cavity extending along at least part of the length of the rod means, a motor operative to rotate the jaws about the axis of the ram, and a drive shaft extending into said cavity and coupled for rotation with the jaws, said motor being operative to drive the drive shaft.

BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the invention will now be described, by way of example only, with reference to the accompanying diagrammatic drawings, in which:

FIG. I is an axial section of a first embodiment of a clam-shell bucket according to the present invention;

FIG. 2 is an axial section of a second embodiment in accordance with the present invention; and

FIG. 3 is a fragmentary section ofa part ofa modified form of the bucket shown in FIGS. 1 and 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The clam-shell buckets shown in the accompanying drawings each include grasping elements in the form of two jaws l, and a ram 2 having a piston rod which extends through the two end walls 3a and 3b of the cylinder 3, the ram being actuable to open and close the jaws l. The bucket is suspended from a beam 4 of an earth-working vehicle via one of the ends of the piston rod. In the embodiments illustrated, a plate 5 is made rigid with the end of the piston rod remote from the jaws I, by means of a key 6. A casing 7 is fixed to the plate 5 by bolts 8 and comprises lugs 9 enabling the assembly to be attached to the beam 4 so as to be pivotally movable about a shaft 10. Moreover, the body 11 of a hydraulic motor is fixed to the casing 7 by screws 21, and the output shaft 12 of this motor is rigid with a pinion 13 meshing with pinion 14 with which a driving rod 15 is rigid. Ducts, 18a and 18b connect the motor 11 to a hydraulic circuit for supplying fluid under pressure, the circuit being known per se.

As regards the embodiment shown in FIG. 1, it is to be noted that the piston rod 16 and the piston 17 of the ram 2 together constitute a single unit.

Ducts 19a and 1917 provided in the piston rod 16 lead respectively into two chambers 20a and 20b in the cylinder 3, one chamber being located on each side of the piston 17; these ducts are connected to a circuit for supplying fluid under pressure, the circuit being known per se.

A bar 22 is rotatably mounted on the end of the piston rod 16 adjacent .to the jaws l by means of an axial and rotary bearing 23. The piston rod 16 comprises an axial cavity 24 and the driving rod 15 extends through the length of the cavity 24. The rod 15 is rigid with a plate, which is fixed to the bar 22 by screws 26. The driving rod 15 is also rotatably mounted in the piston rod 16 by means of two rotary bearings arranged at the two end portions of the piston rod 16.

The jaws l are mounted on the bar 22 so as to be pivotally movable about shafts 27. Lugs 28 are provided which are rigid with the cylinder 3 whereas links 29 are connected at one end to the lugs 28 so as to be pivotally movable about shafts 30 whereas the other end of each link is pivotally connected to a respective one of the jaws I so as to be pivotally movable about a respective shaft 31.

In the embodiment of FIG. 2 the piston rod is not a single unit but comprises two separate parts, an upper part 16a and a lower part 16b, which are mounted rotatably with respect to one another, in a manner known per se, by means of an internal bearing 33 which is both an axial and a rotary bearing.

The upper part of this piston rod has an axial cavity which receives the driving shaft 15, the lower part 16b being solid. The driving shaft 15 is guided inside the part 16 a by means of a rotary bearing 32a, arranged at the level of its upper end, and the driving shaft 15 is fast forrotation with the lower part 16b of the piston rod.

Furthermore, by means of a shaft 34 the bottom end of the bottom part 16b of the piston rod is made rigid with a bar 220. In this case the jaws l are connected to the bar 22a so as to be capable of pivotal movement about shafts 27.

The modification shown in FIG. 3 is applicable to the embodiments FIG. 1 and FIG. 2. In the modification the driving hydraulic motor is a slow-speed motor. For this reason it is not necessary to provide means for reducing the speed of its output shaft 12a; by means of splines 13a, this shaft is made fast for rotation with a sleeve 35 and this sleeve is rigid with the rod 15. The output shaft 12a is coaxial with the cavity 24 in the piston rod 16 or, in the case of the embodiment shown in FIG. 2, coaxial with the cavity 240 in the upper part 160 of the piston rod. Moveover, a cylindrical housing 36 is rigid with the plate 5, whereas the body 11a of the hydraulic motor is itself made rigid with this cylindrical part 36 by means of screws 21a. The hydraulic motor is connected by ducts l8aa and l8bb to a circuit for supplying fluid under pressure, the circuit being known per se. Lugs 9a rigid with the body of the motor are connected to the beam 4 so as to be capable of pivotal movement about the shaft 10.

In the embodiment of FIG. 1, the following components are fast for rotation with one another: the suspension lugs 9, the casing 7, the body 11 of the hydraulic motor, the plate 5 by means of the bolts 8, the piston rod 16 by means of the key 6, and the piston 17. The following components are coupled for rotation with the output shaft of the hydraulic motor; the pinions 13 and 14, the driving rod 15, the plate 25, the bar 22 by means of the screws 26, the jaws 1 by means of the shafts 27, and the cylinder 3 by means of the links 29, the shaft 30 and 31 and the lugs 28. The relative rotation of the output shaft 12 of the motor with respect to the body 11 of the motor therefore makes it possible to adjust the angular orientation of one of the groups of components with respect to the other, and more particularly that of the jaws 1 with respect to the lugs 9 and thus with respect to the beam 4. The sliding movement of the cylinder 3 with respect to the piston rod 16 is of course in no way affected by the said angular orientation.

In the embodiment of FIG. 2, the following components are fast for rotation: the lugs 9, the casing 7, the body 11 of the hydraulic motor, the plate 5 by means of the bolts 8, and the upper part 16a of the piston rod. On the other hand, the following components are fast for rotation with the output shaft 12 of the motor: the pinions l3 and 14, the driving rod 15, the lower part 161) of the piston rod, the bar 22a by means of the shaft 34, and the cylinder 3, by means of the links 29, the shaft 30 and 31 and the lugs 28. The relative rotation of the output shaft 12 of the motor with respect to the body 11 of this motor therefore makes it possible to adjust the angular orientation of one of the groups of components with respect to the other group, and more particularly that of the jaws 1 with respect to the lugs 9, and thus with respect to the beam 4.

In the embodiment of FIG. 1, the rotation of the bar 22 with respect of the piston rod 16 occurs at the level of the bearing 23, whereas in the embodiment of FIG. 2, relative rotation occurs between the lower part 16b and the upper part 16a of the piston rod at the level of the bearing 33. In each case, there is provided means for adjusting the angular orientation of the jaws l with respect to the beam 4.

In the embodiments particularly described, it will be noted that it is not necessary to provide an auxiliary frame, comprising apertures to allow the lugs 28 to slide, for connecting the output shaft of the motor to the jaws 1. Moreover, the rotary driving shaft is at least as well protected against mechanical shocks and dirt, and various other causes of corrosion as the piston rod 16 or the upper part 160 of the piston rod inside which the driving shaft is arranged. Similarly, the pinions l3 and 14 co-operating inside the closing casing 7 are also well protected.

By providing fluid-tight joints at the level of the bearings 32 or of the bearing 320 it is possible to supply fluid under pressure to the lower chamber 20b of the ram 2 directly through the channel defined between the piston rod 16 (or the upper 16a of this rod) and the cavity 24 or 240.

The drive system shown in FIG. 3 is simpler than that of FIGS. 1 and 2. Moreover, it will be apparent that other types of motor can be used instead of hydraulic motors.

The clam-shell buckets particularly described are of relatively simple construction; further no sliding splines are used in the transmission of torque from the shaft 15 because the output shaft 12 of the hydraulic motor and the bar 22 or 22a are arranged at a constant distance from one another which is equal to the fixed length of the piston rod. This possibility is therefore associated with the fact that the piston rod extends through the end walls 3a and 3b of the cylinder 3 and incidentally permits the clam-shell bucket to be suspended from the beam 4. The possibility of obviating the use of sliding splines is advantageous in that it leads to inexpensive and durable constructions.

What is claimed is:

l. A clam-shell bucket comprising grasping elements,

ram means for adjusting the position of said elements, said ram means comprising,

a cylinder having opposed end walls,

piston means slidable in the cylinder, and

piston rod means carried by the piston means, said piston rod means including a central cavity open at at least one end of the piston rod means,

motor means operative to adjust the angular orientation of the grasping elements, said motor means comprising,

a body member, and

a shaft member rotatable relative to the body member, and

rotary driving rod means, one of said members being rigid with an end portion of the piston rod means, and the other of said members being coupled with the driving rod means, said driving rod means extending into the said cavity through the open end thereof.

2. A bucket according to claim 1, further comprising bar means rotatably mounted on the other end portion of the piston rod means and movable axially with the piston rod means, said bar means being connected to the grasping elements and being fast for rotation with the driving rod means, said piston means and said piston rod means constituting a single unit, and the said cavity extending through the entire length of said piston rod means and being open at each end.

3. A bucket according to claim 2, wherein the bar means is movable axially with the driving rod means.

4. A bucket according to claim 2, further comprising bearing means arranged at the end portions of the piston rod means, said bearing means mounting said driving rod means.

5. A bucket according to claim 2, further comprising pivoted links, said links connecting the grasping elements to the cylinder, and said grasping elements being pivotally connected to the bar means.

6. A bucket according to claim 1, wherein the piston rod means comprises first and second relatively rotatable coaxial parts,

said one of said members being rigid with said first parts, said cavity extending through the entire length of said first part and being open at each end. said bucket further comprising bar means, said bar means being rigid with said second part and being connected with the grasping elements, the driving rod means extending through said cavity and being fast for rotation with the second part.

7. A bucket according to claim 6, further comprising bearing means mounting said driving rod means in said cavity, said bearing means being remote from the junction between said first and second parts of the piston rod means.

8. A bucket according to claim 1, wherein the said one member is the body member and the driving rod means is coupled to the shaft member for rotation therewith.

9. A bucket according to claim 8, wherein the shaft member is coaxial with the driving rod means.

10. A clam-shell bucket comprising jaws,

a fluid-actuated ram operative to open and close the jaws, said ram including i a cylinder having opposed end walls, and

piston rod means movable in the cylinder and extending through the end walls, said piston rod means having an axial cavity extending along at least part of the length of the rod means,

a motor operative to rotate the jaws about the axis of the ram, and

a drive shaft extending into said cavity and coupled for rotation with the jaws, said motor being operative to drive the drive shaft. 

1. A clam-shell bucket comprising grasping elements, ram means for adjusting the position of said elements, said ram means comprising, a cylinder having opposed end walls, piston means slidable in the cylinder, and piston rod means carried by the piston means, said piston rod means including a central cavity open at at least one end of the piston rod means, motor means operative to adjust the angular orientation of the grasping elements, said motor means comprising, a body member, and a shaft member rotatable relative to the body member, and rotary driving rod means, one of said members being rigid with an end portion of the piston rod means, and the other of said members being coupled with the driving rod means, said driving rod means extending into the said cavity through the open end thereof.
 2. A bucket according to claim 1, further comprising bar means rotatably mounted on the other end portion of the piston rod means and movable axially with the piston rod means, said bar means being connected to the grasping elements and being fast for rotation with the driving rod means, said piston means and said piston rod means constituting a single unit, and the said cavity extending through the entire length of said piston rod means and being open at each end.
 3. A bucket according to claim 2, wherein the bar means is movable axially with the driving rod means.
 4. A bucket according to claim 2, further comprising bearing means arranged at the end portions of the piston rod means, said bearing means mounting said driving rod means.
 5. A bucket according to claim 2, further comprising pivoted links, said links connecting the grasping elements to the cylinder, and said grasping elements being pivotally connected to the bar means.
 6. A bucket according to claim 1, wherein the piston rod means comprises first and second relatively rotatable coaxial parts, said one of said members being rigid with said first parts, said cavity extending through the entire length of said first part and being open at each end, said bucket further comprising bar means, said bar means being rigid with said second part and being connected with the grasping elements, the driving rod means extending through said cavity and being fast for rotation with the second part.
 7. A bucket according to claim 6, further comprising bearing means mounting said driving rod means in said cavity, said bearing means being remote from the junction between said first and second parts of the piston rod means.
 8. A bucket according to claim 1, wherein the said one member is the body member and the driving rod means is coupled to the shaft member for rotation therewith.
 9. A bucket according to claim 8, wherein the shaft member is coaxial with the driving rod means.
 10. A clam-shell bucket comprising jaws, a fluid-actuated ram operative to open and close the jaws, said ram including a cylinder having opposed end walls, and piston rod means movable in the cylinder and extending through the end walls, said piston rod means having an axial cavity extending along at least part of the length of the rod means, a motor operative to rotate the jaws about the axis of the ram, and a drive shaft extending into said cavity and coupled for rotation with the jaws, said motor being operative to drive the drive shaft. 